[Refactor]: cleanup constants in codebase so they are in one place

### zot version

v2.1.10

### Describe the bug

There are various default constants which should be located in one common place.
pkg/api/constants
pkg/storage/constants
pkg/extensions/.../constants/

### To reproduce

1. Configuration
2. Client tool used
3. Seen error


### Expected behavior

_No response_

### Screenshots

_No response_

### Additional context

_No response_